Stressful Life Events Are Related to More Negative Interpretations, but Not Under Acute Stress

Studies have identified deleterious effects of stress on multiple cognitive processes such as memory and attention. Little is known about the impact of stress on interpretation. We investigated how an induced acute stress and more long-term stress related to life events were associated with interpretations of ambiguous stimuli. Fifty participants answered a questionnaire indexing the number of stressful life events. A median split was used to compare those reporting few or more events. Half of participants performed an arithmetic task that induced acute stress; they were compared to a control group performing a less stressful task. We measured the interpretation of ambiguous visual stimuli, which participants had to judge as “negative” or “positive”. We found a significant interaction between the number of stressful life events and the induced acute stress on the proportion of positive interpretations. In the control group, participants reporting more stressful events produced less positive interpretations than those reporting few events. In the induced stress condition, no significant difference was found. Life events tend to influence interpretation in the absence of an acute stressor, which seems to be more influent in the short term.

In the face of stress: Interpreting individual differences in stress-induced facial expressions

Stress is an inevitable part of life that can profoundly impact social and emotional functioning, contributing to the development of psychiatric disease. One key component of emotion and social processing is facial expressions, which humans can readily detect and react to even without conscious awareness. Facial expressions have been the focus of philosophic and scientific interest for centuries. Historically, facial expressions have been relegated to peripheral indices of fixed emotion states. More recently, affective neuroscience has undergone a conceptual revolution, resulting in novel interpretations of these muscle movements. Here, we review the role of facial expressions according to the leading affective neuroscience theories, including constructed emotion and social-motivation accounts. We specifically highlight recent data (Mayo et al, 2018) demonstrating the way in which stress shapes facial expressions and how this is influenced by individual factors. In particular, we focus on the consequence of genetic variation within the endocannabinoid system, a neuromodulatory system implicated in stress and emotion, and its impact on stress-induced facial muscle activity. In a re-analysis of this dataset, we highlight how gender may also influence these processes, conceptualized as variation in the "fight-or-flight" or "tend-and-befriend" behavioral responses to stress. We speculate on how these interpretations may contribute to a broader understanding of facial expressions, discuss the potential use of facial expressions as a trans-diagnostic marker of psychiatric disease, and suggest future work necessary to resolve outstanding questions.

Animacy and attentional processes: Evidence from the Stroop task

In visual perception, evidence has shown that attention is captured earlier and held longer by animate than inanimate stimuli. The former are also remembered better than the latter. Thus, as far as attentional processes are concerned, animate entities have a privileged status over inanimate entities. We tested this hypothesis further using an adaptation of the Stroop paradigm. Adults had to categorise the colours of words that referred to either animate or inanimate concepts. In two experiments, we found that it took longer to process the ink colour of animate than inanimate words. Indeed, this effect was found when the words were presented in an oral animacy Stroop task (Experiment 1) and in a manual animacy Stroop task (Experiment 2). Using ex-Gaussian analyses and examining the distribution of RTs as a function of vincentiles per animacy condition, we did not find a specific localisation of the animacy effect. The findings are interpreted as providing further evidence that animates are prioritised in processing because their fitness value is higher than that of inanimates.

From Anxious to Reckless: A Control Systems Approach Unifies Prefrontal-Limbic Regulation Across the Spectrum of Threat Detection

Here we provide an integrative review of basic control circuits, and introduce techniques by which their regulation can be quantitatively measured using human neuroimaging. We illustrate the utility of the control systems approach using four human neuroimaging threat detection studies (N = 226), to which we applied circuit-wide analyses in order to identify the key mechanism underlying individual variation. In so doing, we build upon the canonical prefrontal-limbic control system to integrate circuit-wide influence from the inferior frontal gyrus (IFG). These were incorporated into a computational control systems model constrained by neuroanatomy and designed to replicate our experimental data. In this model, the IFG acts as an informational set point, gating signals between the primary prefrontal-limbic negative feedback loop and its cortical information-gathering loop. Along the cortical route, if the sensory cortex provides sufficient information to make a threat assessment, the signal passes to the ventromedial prefrontal cortex (vmPFC), whose threat-detection threshold subsequently modulates amygdala outputs. However, if signal outputs from the sensory cortex do not provide sufficient information during the first pass, the signal loops back to the sensory cortex, with each cycle providing increasingly fine-grained processing of sensory data. Simulations replicate IFG (chaotic) dynamics experimentally observed at both ends at the threat-detection spectrum. As such, they identify distinct types of IFG disconnection from the circuit, with associated clinical outcomes. If IFG thresholds are too high, the IFG and sensory cortex cycle for too long; in the meantime the coarse-grained (excitatory) pathway will dominate, biasing ambiguous stimuli as false positives. On the other hand, if cortical IFG thresholds are too low, the inhibitory pathway will suppress the amygdala without cycling back to the sensory cortex for much-needed fine-grained sensory cortical data, biasing ambiguous stimuli as false negatives. Thus, the control systems model provides a consistent mechanism for IFG regulation, capable of producing results consistent with our data for the full spectrum of threat-detection: from fearful to optimal to reckless. More generally, it illustrates how quantitative characterization of circuit dynamics can be used to unify a fundamental dimension across psychiatric affective symptoms, with implications for populations that range from anxiety disorders to addiction.

Left medial orbitofrontal cortex volume correlates with skydive-elicited euphoric experience

The medial orbitofrontal cortex has been linked to the experience of positive affect. Greater medial orbitofrontal cortex volume is associated with greater expression of positive affect and reduced medial orbital frontal cortex volume is associated with blunted positive affect. However, little is known about the experience of euphoria, or extreme joy, and how this state may relate to variability in medial orbitofrontal cortex structure. To test the hypothesis that variability in euphoric experience correlates with the volume of the medial orbitofrontal cortex, we measured individuals' (N = 31) level of self-reported euphoria in response to a highly anticipated first time skydive and measured orbitofrontal cortical volumes with structural magnetic resonance imaging. Skydiving elicited a large increase in self-reported euphoria. Participants' euphoric experience was predicted by the volume of their left medial orbitofrontal cortex such that, the greater the volume, the greater the euphoria. Further analyses indicated that the left medial orbitofrontal cortex and amygdalo-hippocampal complex independently explain variability in euphoric experience and that medial orbitofrontal cortex volume, in conjunction with other structures within the mOFC-centered corticolimbic circuit, can be used to predict individuals' euphoric experience.

Benefits of using culturally unfamiliar stimuli in ambiguous emotion identification: A cross-cultural study

A novel emotion recognition task that employs photos of a Japanese mask representing a highly ambiguous stimulus was evaluated. As non-Asians perceive and/or label emotions differently from Asians, we aimed to identify patterns of task-performance in non-Asian healthy volunteers with a view to future patient studies. The Noh mask test was presented to 42 adult German participants. Reaction times and emotion attribution patterns were recorded. To control for emotion identification abilities, a standard emotion recognition task was used among others. Questionnaires assessed personality traits. Finally, results were compared to age- and gender-matched Japanese volunteers. Compared to other tasks, German participants displayed slowest reaction times on the Noh mask test, indicating higher demands of ambiguous emotion recognition. They assigned more positive emotions to the mask than Japanese volunteers, demonstrating culture-dependent emotion identification patterns. As alexithymic and anxious traits were associated with slower reaction times, personality dimensions impacted on performance, as well. We showed an advantage of ambiguous over conventional emotion recognition tasks. Moreover, we determined emotion identification patterns in Western individuals impacted by personality dimensions, suggesting performance differences in clinical samples. Due to its properties, the Noh mask test represents a promising tool in the differential diagnosis of psychiatric disorders, e.g. schizophrenia.

Parachuting and pregnancy: what do we know about pregnant skydivers and the risks they are taking?

OBJECTIVE

There is little medical knowledge about the risks of skydiving during pregnancy. Some national parachuting associations ask for a doctor's permission; others recommend not jumping at all during pregnancy. This article provides survey data and a literature review of pregnancy and parachuting/skydiving related issues to help the pregnant skydiver and her obstetrician make an informed decision. Survey data presented include pregnancy, delivery, and parachuting information from skydivers who jumped during pregnancy.

DESIGN

International retrospective anonymous online questionnaire considering the Checklist for Reporting Results of Internet E-Surveys (CHERRIE). The PubMed database was searched with using the terms "skydive," "pregnancy," and "parachute" (query April 2013).

SETTING

Web page questionnaire on skydivers' epidemiology, experience, and pregnancy-related information.

PARTICIPANTS

Fifty-seven parous female skydivers.

ASSESSMENT OF RISK FACTORS

Information on athletes' experience, weather conditions, obstetric history (gravida, gestational week), delivery mode was obtained.

MAIN OUTCOME MEASURES

Epidemiology of pregnant skydivers and literature review to provide information on skydiving risks.

RESULTS

Women do actively decide to skydive while pregnant. The majority of our participants were between 25-year-old and 35-year-old primips with 100 to 1000 jumps experience, answering the questionnaire from a European IP address. Precautions are taken in terms of weather conditions, gear, or sports partner. The literature review found no relevant literature regarding the question. Literature is searched for risk factors that come close to the ones in skydiving (ie, oxygen saturation, shock forces, and others). Further studies are needed to show the long-term effect of stress or low O2 saturation on antenatal programming, or short-term hypoxia and pregnancy outcome in pregnant skydiving women and their offspring.

CONCLUSIONS

Pregnancy itself is a risk factor for injuries. Injuries in pregnancy are clearly associated with an unfavorable pregnancy outcome. The recommendation "do not skydive during pregnancy" is the safest approach. A possible lesser risk alternative to skydiving could be wind-tunnel training.

CLINICAL RELEVANCE

This article provides insights into the pregnant skydiver's decision making regarding the sports. In combination with the literature review, we provide up-to-date easy to understand information on the possible risk factors. This is a valuable source of information for the care providers of female skydivers to understand and compare the risk factors of this sport. With this information, the professional recommendation and relationship are strengthened. This article also guides the need for further research. Possible research areas include pregnancy and sports-related risk factors, placentation and prenatal programming, physical and psychological factors associated with skydiving.

Acute psychosocial stress and emotion regulation skills modulate empathic reactions to pain in others

Psychosocial stress affects resources for adequate coping with environmental demands. A crucial question in this context is the extent to which acute psychosocial stressors impact empathy and emotion regulation. In the present study, 120 participants were randomly assigned to a control group vs. a group confronted with the Trier Social Stress Test (TSST), an established paradigm for the induction of acute psychosocial stress. Empathy for pain as a specific subgroup of empathy was assessed via pain intensity ratings during a pain-picture task. Self-reported emotion regulation skills were measured as predictors using an established questionnaire. Stressed individuals scored significantly lower on the appraisal of pain pictures. A regression model was chosen to find variables that further predict the pain ratings. These findings implicate that acute psychosocial stress might impair empathic processes to observed pain in another person and the ability to accept one's emotion additionally predicts the empathic reaction. Furthermore, the ability to tolerate negative emotions modulated the relation between stress and pain judgments, and thus influenced core cognitive-affective functions relevant for coping with environmental challenges. In conclusion, our study emphasizes the necessity of reducing negative emotions in terms of empathic distress when confronted with pain of another person under psychosocial stress, in order to be able to retain pro-social behavior.